Court: Roadside drunken driving tests not valid for pot

The highest court in Massachusetts has ruled that field sobriety tests typically used in drunken driving cases cannot be used as conclusive evidence that a motorist was operating under the influence of marijuana.

The Supreme Judicial Court on Tuesday said police officers could testify only to their observations about how a person performed during a roadside test. But they would not be allowed to testify as to whether a person passed or failed such a test or offer their own opinions about whether a driver was too high to drive.

The justices said there is currently no reliable scientific test for marijuana impairment.

Adult use of recreational marijuana is now legal in Massachusetts, though the court noted it's still illegal to drive while high on pot.